Alluvial-transported soil, Biology

Assignment Help:

Alluvial

Materials of this catego~ya re deposited by running water in the form offroodplains, river terraces, deltas and alluvial fans. These deposits have two outstanding characteristics by, which they can usually be recognised with ease. Fit, the individual particles tend to be rounded and smootlfed by the action of running water. Second, the layers are usually distinct in that each contain particles of a particular range or size class depending upon the speed of the transporting water. Coarse materials are laid by swift water currents, whereas, fine particles are deposited by relatively calm waters.

Alluvial soils are found bo~deringri vers and slow moving bodies of water. When first formed; these deposits are sa low that they are frequently flooded at high-water stages, and at such times they receive additional increments of fine sediment, especially if they are well vegetated. At this stage of development, they are called flood plains. As the stream cuts its channel deeper, the flood plain is left above the reach of high water and is called a terrace. Large streams are frequently bordered by a series of terraces, the oldest being at considerable heights above the present water level.

Where streams enter a lake or a sea, the deposit of silt and clay that settles down at the edge of the still water may build a delta which gradually lengthens until it extends beyond the mouth of the stream. The Sunderbans in West Bengal and Bangladesh are examples of deltas, which supprt mangrove type of vegetation. Alluvial fans are formed where a stream descends from uplands, and a sudden change in gradient may sometimes occur as the stream emerges at the lower level. Deposition of sediments is thereby forced, giving rise to alluvial fans. They differ from a delta in their location and in the character of their debris. Fan material is often gravel and stony in nature
and is well drained.

Among the transported soils, the alluvial soils of the Indoagetic Plains are highly productive and have been under'cultivation for several thousands of years. The parent material of the Indo-Gangetic alluvial soils is actually in the Himalayas. Mountain and hill washes contribute huge quaiitities of sediments brought down by the rivers and deposited in the plains below. Most of the alluvial soils are under intensive crop cultivation.


Related Discussions:- Alluvial-transported soil

How does the excretory system of nematodes work, How does the excretory sys...

How does the excretory system of nematodes work? The metabolic residuals of nematodes are collected by two longitudinal lateral excretory channels that open in one excretory po

Define drug effects on lipid metabolism, Define Drug effects on Lipid Metab...

Define Drug effects on Lipid Metabolism? Drugs can affect the metabolism of various essential nutrients in the body. These impairments are highlighted herewith: Lipid metabo

Describe technique operation prosthetic valve endocarditis, Describe the Te...

Describe the Technique of Operation in prosthetic valve endocarditis? The operative principle is drainage of abscess, removal of debris and valve rep or replacement to reverse

What is light reaction, What is light reaction? Light reactions are rea...

What is light reaction? Light reactions are reactions, which are initiated by light (also photo-induced reactions). Usually, light energy is change into chemical energy.

Explain bidirectional superior vena cavo, Explain Bidirectional Superior ve...

Explain Bidirectional Superior vena cavo pulmonary shunt bidirectional glenn "This is a palliative produce where blood from superior vena cava is diverted to the pulmonary arter

Periodicity - qualitative characters, Periodicity (Phenology, Aspection) ...

Periodicity (Phenology, Aspection) It refers to the study of seasonal changes in the community, that is, the periodic phenomena of organisms in relation to their climate. Peri

Define the term- species, What is a species? A species is a set of livi...

What is a species? A species is a set of living beings able to cross between themselves generating fertile offspring. This concept though does not apply to individuals of ex

Colibacillosis of newborn animals, Colibacillosis of newborn animals T...

Colibacillosis of newborn animals This is the commonest disease entity of newborn farm animals. In calves the disease  occurs in three forms, viz. enteric colibacillosis manif

Why dietary obtainment of iodine important for thyroid, Q. Why is the dieta...

Q. Why is the dietary obtainment of iodine so important for thyroid functioning? The obtainment of iodine from the diet is vital for the thyroid because this chemical element i

Explain cardiac muscle or heart muscle, Explain Cardiac Muscle or heart mus...

Explain Cardiac Muscle or heart muscle? Cardiac muscle, or heart muscle, is a striated muscle that occurs only in the vertebrate heart. The heartbeat is controlled by noncontr

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd